By Alan Levin and Harry Suhartono Bloomberg News
As the crew of Lion Air struggled to control its dive Boeing Co. 737 Max 8, they received help from an unexpected source: an off-site pilot who happened to ride in the cockpit. who sat in the cockpit seat correctly diagnosed the problem and told the crew how to deactivate the inadequately functioning flight control system and save the plane, according to two people familiar with the Indonesian investigation.
The next day, under the command of a different crew that the investigators claim to be an identical malfunction, the same jet hit the dock, killing all 189 on board.
Earlier undisclosed details of Lion Air's earlier flight are a new key in the mystery of how some 737 Max pilots faced with the malfunction managed to prevent a disaster while others lost control of their aircraft and crashed. The presence of a third pilot in the cockpit was not contained in the report of the Indonesian National Transport Safety Committee of 28 November on the accident and has not been reported previously. Bali in Jakarta told the crew to interrupt the engine power to snap the nose down, according to familiar men, a part of a checklist that all pilots should remember.
"All the data and information we have about the flight and the plane was presented to the Indonesian NTSC. At this stage, we can not provide further comments due to the ongoing investigation of the incident, "Leonard spokesman Danang Prihantoro said on the phone.
Indonesia's Safety Committee report said the plane had had multiple failures in previous flights and did not have
Boeing representatives and the Indonesian Safety Committee refused to comment on the earlier flight.
The safety system designed to keep airplanes climbing too steeply and stopping is subject to control by the crash investigators. and then less than five months later in Ethiopia. It is believed that the malfunction sensor has tricked Lion Air's computers into thinking that it is necessary to automatically push the nose to avoid collapse. crash during the March 10th crash investigation of Ethiopian Airlines flight 302.
Following the two incidents, questions arose about approving the design of the new Boeing 737 model. The General Inspector of the Department of Transport examines how the aircraft is certified to fly, and the big jury at the US Department of Justice is also seeking records of a possible criminal verification of the airplane certification.
The FAA announced that it plans to impose changes to the system so that it is less likely to be activated when there is no emergency. The Agency and Boeing said they would need additional training and referrals to it in the flight manuals.
"We will cooperate fully with the Department of Transport Audit Review," said Boeing spokesman Charles Bikers in an email. After the crash of Lion Air, two American pilot allies said the potential risks of the system, known as the Shift Enhancement System, or MCAS, were not well written. in their guides or training.
"None of the documentation for the Max aircraft contains an explanation." We do not like being unannounced, "said John Wax, president of the Southwest Airlines pilots." That makes us ask, "Is that all, guys?" I hope there are no more surprises there.
Following the crash of Lion Air, the FAA requires Boeing to notify the airlines of the system and Boeing sends it to the Airline. bulletin of all Customers who fly by Max remind them how to deactivate them in case of emergency
The authorities are released little details of Ethiopian Airlines flight 302, except that they had "a very similar" run as Lion Air and then dropped to the ground, and there were no reports of maintenance problems with Ethiopian Airlines before the crash  If it turns out that the same problem has helped eliminate Ethiopian Airlines's 302 flight, one of the most unpleasant questions of aviation security investigators and aviation consultants is why the pilots of this flight have not done the checklist that deactivates the system. "After this horrendous incident with Lion Air, you would think that anyone who flies on this plane will know that this is the way you exclude it," said Steve Wallace, former director of the Accident Investigation US Federal Aviation Administration
The combination of factors required to take down an airplane under these circumstances suggests that other issues may have arisen in the catastrophe in Ethiopia, said Jeffrey Gucceti, who also led an accident investigation at the FAA and now is a consultant.
"It is simply implausible that this MCAS deficiency alone can reduce the modern jet
MCAS is driven by a sensor near the nose that measures the so-called angle of attack or whether the air flows parallel to the length the fuselage or at an angle. During the Lion Air flight, the angle-of-attack sensor failed and sent false indications showing that the airplane's nose was pointing dangerously upward.